1. Field of the Invention
The invention relates generally to beverage machines, and more particularly, to devices and methods for producing and dispensing products that are susceptible to growth of microbiological organisms.
2. Description of Related Art
Systems for producing beverages, such as frozen carbonated beverage machines, are well known in the art. These devices produce a frozen beverage by freezing a mixture of ingredients such as syrup, water and carbon dioxide in a mixing, or freezing, chamber. The mixture freezes on the inner surface of the refrigerated mixing chamber. Typically, the mixing chamber is surrounded by a helical coil through which a refrigerant passes. A beater is disposed inside the chamber, which includes a rotating shaft having a plurality of outwardly-projecting blades that scrape the mixture off the inside wall of the mixing chamber. Once the beverage is in the desired frozen state, the product is dispensed from the chamber through a product dispensing valve.
Frozen beverage machines referred to as xe2x80x9copen hopperxe2x80x9d or xe2x80x9copen bowlxe2x80x9d design machines are typically used to dispense low acid frozen beveragesxe2x80x94having a pH level that supports potential growth of micro organisms. The product is poured from a previously sealed or refrigerated package directly into the hoppers, which are also refrigerated. In so doing, any contaminants that are introduced will have their growth retarded by the low temperatures. This is similar to placing milk in a refrigerator.
While these existing machines can retard the growth of contaminants, the contaminants do continue to grow and the hoppers are exposed to air-borne contaminates, so the machines must be sanitized on a periodic basis. This typically requires the machines to be disassembled on a daily or frequent basis and cleaned with sanitizing solution. A more extensive cleaning may be required on a weekly or less frequent basis. Some machines that are open hopper design have a heating process built in that raises the product contained in the hopper to an elevated temperature in order to pasteurize the product and reduce the contaminant level. This is somewhat effective, but has a negative effect on the quality of the product to be dispensed. Also, the unit must be removed from service on a relatively frequent basis and disassembled and sanitized. Moreover, the reliability of the disassembly and cleaning process is often low due, as unskilled and under-trained individuals are often required to complete this process.
The present invention addresses shortcomings of the prior art.
The present invention addresses some of these issues associated with the prior art and significantly reduces the contamination exposure and subsequent growth of contaminants by the provision of a sealed machine with a sealed delivery system. It will minimize any exposure to contaminants while keeping the mixture refrigerated in order to retard growth of any small amounts of contaminants that may enter the sealed system.
The system and methods according to the present invention are particularly suited in processing beverages that are subject to microbiological contamination and growth, such as milk products or other protein based beverages or simple sugar based beverages. Further, while the present invention is disclosed primarily in terms of frozen beverages, it is applicable to any containerized or flow system.
In one embodiment of the invention, a completely sealed unit (though the invention is also applicable to non-sealed units) relies on keeping contaminants from entering the system and keeping any syrup mixtures that are susceptible to rapid bacteriological growth chilled so that growth is significantly retarded. This reduces the frequency of sanitizing required. Since the system is sealed, the sanitizing can occur without the time consuming and inconsistent disassembly that must occur on open hopper machines. An automated, on-board sanitation system that is computer controlled is provided that is activated, for example, in response to an operator""s action such as activating a button, or upon predetermined criteria such as the passage of a certain time period.
In some embodiments, sanitizing additionally occurs by a similar process used for producing frozen beverages. A bag or container of sanitizing solution is attached to the machine in much the same way the syrup mixture is attached and the sanitizing solution is pumped throughout the delivery and freezing areas sanitizing all surfaces contacted by the potentially contaminated syrup solution.
In accordance with aspects of the present invention, a frozen beverage machine includes a process control block having a plurality of inlets for receiving ingredients and a plurality of outlets. A mixing block has a plurality of inlets connected to the process control block outlets such that ingredients flowing through the mixing block are mixed together therein. At least one freezing chamber is connected to the mixing block outlet to receive the mixed ingredients therefrom, and a refrigeration system is arranged to refrigerate the freezing chamber. In some embodiments, the mixing block directly contacts the freezing chamber and is chilled through such contact. In other embodiments, the mixing block is situated remotely from the freezing chamber and chilled independently. A controller, which typically includes a microprocessor and associated memory, is connected to the process control block and is operable to control operation of the frozen beverage machine. A dispensing valve is connected to the freezing chamber to dispense product from the freezing chamber.
In addition to controlling the operation of the frozen beverage machine to produce beverage products, the controller is programmed to sanitize the frozen beverage machine in an automated fashion. At least one of the mixing block inlets is connected to a source of cleaning fluid, which may be contained in the frozen beverage machine or external thereto. The product mixture is drained from the freezing chamber via a drain valve, and the cleaning solution is pumped into the cleaning solution inlet of the mixing block and into the freezing chamber. After the machine is sanitized, the cleaning solution is drained from the freezing chamber via the drain valve. The draining of product mixture or cleaning solution may be accomplished, for example, by pressurizing the freezing chamber and opening the drain valve, and/or by pumping the materials from the freezing chamber through the drain valve.